need read-write lock in objective c or c

Question

I can't seem to find any read-write locks for Objective C. This is for iphone dev. Any ideas? The appendix in this paper has some code, but it is incomplete.

score 0 · Answer 1 · answered Apr 28 '11 at 19:06

0

Foundation provides NSLock to help you lock and unlock threads but I think it could help you.

answered Apr 28 '11 at 19:06

albianto

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And `NSRecursiveLock` for recursive locking. Most use cases are easier to implement with recursive locks. :) – Jonathan Grynspan Apr 28 '11 at 19:11
1

Thanks, but I need a *readers-writer* lock, not just any old lock – Jacko May 01 '11 at 00:52
2

I searched along internet, I think you can only use pthread_rwlock_t and its related commands – albianto May 01 '11 at 04:06

score 0 · Answer 2 · answered Dec 07 '21 at 10:02

You can use dispatch_barrier_async function and a concurrent queue to implement a read-write lock.

    dispatch_queue_t queue = dispatch_queue_create("your queue name", DISPATCH_QUEUE_CONCURRENT);
    dispatch_async(queue, ^{
        // execute read task 1
    });
    dispatch_async(queue, ^{
        // execute read task 2
    });
    dispatch_barrier_async(queue, ^{
        // execute write task 1
    });

need read-write lock in objective c or c

2 Answers2